1. Field of the Invention
The present invention relates to a motor. More particularly, the present invention relates to a stator of a motor which is simple in structure and can reduce manufacturing costs because it does not need to apply an insulator or an insulation film in order to insulate a teeth part of a stator core.
2. Background Art
In general, a motor includes a stator and a rotor which is located and rotated on the outer circumference or the inner circumference of the stator. The stator includes a rounded base and a stator core having a plurality of teeth which are radially formed in the outer circumferential direction or in the inner circumferential direction of the base.
In order to wind a coil on the teeth, the surface of the stator core including the teeth must be insulated. In order to insulate the surface of the stator core, an insulator made of an insulating plastic material is connected to the stator core, the surface of the stator core is insulation-coated using insulating powder, or an insulation film made of insulating resin is inserted into a slot between the teeth.
In the meantime, in case of a motor used to rotate a tub of a washing machine, in order to connect the motor having the stator to a washing machine body, a connection part protruding in the central direction is formed on the inner face of the stator. As described above, the technology to form the stator on the connection part is disclosed in Korean Patent Nos. 10-301492 (prior art reference 1), 10-0808194 (prior art reference 2), and 10-1135333 (prior art reference 3).
In case of the stator disclosed in the prior art reference 1, in order to form the connection part, connection parts are respectively formed and blanked on each of stator core sheets, and then, the stator core sheets are laminated to complete a stator core and form the connection parts.
In case of the prior art reference 2, insulators are connected to the upper and lower parts of the stator core and connection parts are formed on each of the insulators in such a manner that the connection parts are formed when the upper and lower insulators are respectively connected to the stator core.
In case of the prior art reference 3, L-shaped connection parts are attached to the inner face of the stator core, and then, insulating powder is coated on the entire surface of the stator.
However, in case of the prior art reference 1, because the connection parts must be formed on the stator core sheets, lots of electric steel sheets are required and there are a lot of scraps to be thrown out. Moreover, the prior art reference 2 can be applied to the case that the stator core sheets are laminated one by one but cannot be applied to a spiral core of a type that the stator core is wound in a spiral form.
The prior art reference 2 needs a mold for manufacturing an insulator, and is restricted in the number of windings of the coil because the size of the slot formed between the teeth is reduced by the thickness of the insulator, and hence, electromagnetic characteristics necessary for the stator may fall short of users' demands. Furthermore, the prior art reference 2 causes increase of the manufacturing costs due to an increase of the usage of plastic resin for forming the connection parts.
In case of the prior art reference 3, because the insulating powder is coated after the L-shaped connection parts are connected, the insulating powder is coated on the entire surface of the stator, and hence, it causes an increase of the usage of insulation coating. Additionally, in order to attach the L-shaped connection parts, welding is generally used, but such welding method does not guarantee a firm connection of the L-shaped connection parts.
Therefore, the inventors of the present invention propose a stator of a motor having a new structure which can solve the above-mentioned problems and can firmly connect a hall sensor assembly.